Charlie is sick!

I think Charlie is sick. He's been crouching like this since I came back from work this afternoon (the picture was taken just now at 8.30 p.m.). I wonder why... He's not as playful and cheerful as usual. I realised something was wrong when he didn't greet me at the gate when I came home. I'm very worried...he won't even let me caressed him and he refused to eat his food until now. What's wrong with him? Charlie,Charlie...hope you'll get well soon. Aqeel and 'Adnin want to play with you.